Objective: To investigate the bio-fabrication of silver nanoparticles (AgNPs) using aqueous leaf extract of Melia dubia (ALM) and test the antifungal activity of AgNPs against pathogenic fungi Aspergillus niger and Candida tropicalis.

Methods: 10 ml of aqueous leaf extract of Melia dubia was added to 90 ml of 1 mM silver nitrate and incubated for 8h at room temperature. After incubation, the color change was observed from light yellow to dark brown. The synthesized AgNPs were characterized using UV-Vis spectroscopy, Fourier Transform Infra red spectroscopy (FTIR), Energy Dispersive X-ray Spectroscopy (EDX), Scanning Electron microscopy (SEM), X-ray diffraction analysis (XRD) and Atomic Force Microscopy (AFM). Antifungal activity against Aspergillus niger and Candida tropicalis was carried out by employing the disc diffusion method.

Results: UV-Vis spectra confirmed the synthesis of AgNPs by showing characteristic peak between 380-450 nm*. FTIR spectra showed the functional groups possibly involved in the synthesis of AgNPs. EDX confirms the presence of elemental silver at 3 Kev. SEM and AFM showed the synthesized AgNPs were spherical in shape with size ranging between 20-40 nm*. XRD analysis revealed the crystalline nature of AgNPs with face centred cubic (FCC) lattice. AgNPs was found to be very effective against the tested pathogenic fungi A. niger and C. tropicalis and formed the inhibition zones 13.0 and 14.5 mm respectively.

Conclusion: It is concluded that the bio-fabrication of AgNPs using aqueous leaf extract of Melia dubia was robust and rapid. The AgNPs were stable and proved to be excellent antifungal agents.